, oklahoma. >>> tonight vice president joe biden's son, beau, is spending the night at the m.d. cancer center in houston. beau biden, the attorney general of delaware, went with his father for tests this morning after feeling weak and disoriented on a family vacation last week. he was seen at dinner last night with his father, but people close to the bidens told nbc news the family is taking this quite seriously. chief medical editor dr. nancy snyderman is here with more. nancy, we don't know exactly what's going on here, but he did suffer a stroke three years ago when he was 41 years old. typically with a stroke patient, experience more problems down the line. >> well, typically one-quarter of those stroke patients have had symptoms before. and we do know that since his strike, beau biden has had several episodes in the past. and that makes this serious. we have established tonight, nbc news has confirmed that he has been admitted to m.d. anderson for further testing. and having already been seen at two major medical centers around the country and now at m.d. anderson, the procedure that he'